Windmills show up, creating electrical power.A small house with antenna zapping electricity everywhere.If an electric type gets hit by the zaps it's power is boosted.
Everything sinks because of a flood.This gives advantages to water Pokemon, because they can swim right throught it.Every now and then a small flood will come.
A garden-like field comes that's filled with flowers, grass, and other plants.This gives advantages to Grass, Poison, and Bug Pokemon.It gives them things such as trees to hide in. There are also occasional berries that grow.
A giant volcano sprouts and erupts regular fire.This higly boosts fire type Pokemon.And a definite disadvantage of Grass type due to the volcano.
High winds come now and then in the air field. The wind is unpredictable. It has clouds in the sky making it hard to see for any of the pokemon in the air and the pokemon not in the air won't be able to see the ones in the sky. It is a tower high in the air.